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Polychlorinated naphthalenes (PCNs) consist of naphthalene substituted with 1-8 chlorines, yielding 75 possible congeners. They were formerly used in industry, occur at trace levels in commercial PCB mixtures, and have current sources in combustion processes. PCNs are widespread in arctic air with higher levels in the European Arctic. Concentrations were higher during the cold months in arctic Canada and Russia, but no seasonality was noted in subarctic Canada and Greenland. "Marker" congeners indicative of combustion were evident at some sites. Total toxic equivalents (TEQ) in air due to PCNs+dioxin-like PCBs were dominated by PCNs in arctic Canada and Russia, but not in subarctic Canada. Deposition of PCNs in snow was measured in northern Norway and Svalbard. Surveys of PCNs in the lower food web are limited to the northern Baltic Sea and lakes/rivers of northern Scandinavia. PCNs showed little or no biomagnification in lower food webs of the northern Baltic and discrimination among congeners suggested preferential metabolism. There are no reports of PCNs in fish and invertebrates from the Arctic Ocean, and only one from Antarctica. Total PCNs in marine mammals followed the order: harbour seal~pilot whale>or=polarbear>beluga>ringed seal~Weddell seal. Total PCNs in seabirds varied over 100-fold, with higher concentrations in glaucous gull eggs and plasma from Bear Island, and livers of northern fulmar from the eastern Canadian Arctic. Lower concentrations occurred in eggs of glaucous gull from Svalbard and black-backed gull from the Faroe Islands. PCNs accounted for <1% of total TEQ in ringed seal, Weddell seal, seabirds and polar bear, but up to 6-15% in beluga and pilot whale. TEQ due to PCNs were generally low in harbour seal, but up to 9% of total TEQ in some animals., (Crown Copyright 2009. Published by Elsevier B.V. All rights reserved.)

The concentrations of Cd, Co, Cu, Ni, Pb and Zn were determined in the Antarctic copepods Rhincalanus gigas (Brady, 1883), Calanus propinquus (Brady, 1883), Calanoides acutus (Giesbrecht, 1902), Metridia curticauda (Giesbrecht, 1889) and Metridia gerlachei (Giesbrecht, 1902). Samples were taken at seven different stations between 18.01.1999 and 19.02.1999. Metal concentrations in biological tissue were determined by graphite furnace atomic absorption spectroscopy (GFAAS) with Zeeman background correction and by flame AAS (air-acetylene) with deuterium background correction. We found high mean Cd concentrations in the Metridia species of about 10 microg Cd g(-1) and 3-6 microg Cd g(-1) in the other copepods. Co and Pb concentrations were low in all species investigated (<0.1 microg Co g(-1) and <1 microg Pb g(-1)). Zn concentrations were high in M. gerlachei and R. gigas (518 and 430 microg Zn g(-1)). In comparison to copepods from Arctic Seas (Fram Strait, Greenland Sea) and the North Sea, Cd and Cu concentrations appear higher in Antarctic copepods, while Ni and Pb concentrations are similar in both polar regions and Pb concentrations are higher in the North Sea. Variability between species and different regions are discussed.

Captive emperor penguins in Antarctica hand-fed Antarctic krill assimilated an average of 70.5% +/- 1.7% (n = 3) of the energy in the diet. Water intake estimated by tritiated water turnover was 9.4% +/- 2.4% less than that measured gravimetrically. Tritium took 1.5 h from injection to equilibrate with the penguins' body water pools.

To examine the presence of metabolic cold adaptation in Antarctic isopods, whole animal rates of oxygen uptake (MVo2) and protein synthesis were measured in Glyptonotus antarcticus at 0 degree C and compared with the temperature isopod Idotea rescata at 4 and 14 degrees C. The specific relationship between rates of metabolism and protein synthesis was investigated by injecting animals with cycloheximide, a protein synthesis inhibitor. In G. antarcticus, routine MVo2 was 11.10 +/- 0.89 mumol.kg-1.min-1 (n = 19 animals), and ks was 0.24 +/- 0.04% protein synthesized/day (n = 8 animals). Comparison with I. rescata showed that standardized whole animal MVo2 decreased with temperature (temperature quotient = 1.99), but whole animal ks was considerably lower in the Antarctic isopod; 66 and 22% of total MVo2 was attributable to protein synthesis in G. antarcticus at 0 degree C and I. rescata at 4 degrees C, respectively. The energetic cost of protein synthesis was four times higher in G. antarcticus at 885 +/- 141 mmol ATP/g protein (n = 5 animals) compared with 237 +/- 76 mmol ATP/g protein (n = 6) in I. rescata. G. antarcticus does not show metabolic rate compensation and maintains extremely low ks levels because of the relatively high energetic cost of protein synthesis.